This application claims the priority of Korean Patent Application No. 2002-69412, filed on Nov. 9, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a computer network, and more particularly, to a method and apparatus for determining a communication path over a network by using a spanning tree and circuit detection.
2. Description of the Related Art
Among a variety of methods of determining communication paths among a plurality of devices over a network, spanning tree protocol (STP) has been suggested as IEEE standard 802.1D in order to solve a problem of traffic loops generated by interconnecting different local area networks (LANs). STP has been generally used for solving the problem of looping using bridges over a network. In accordance with the advent of communication markets, demands for networks connecting main offices and their branch offices, customers and businesses, and businesses and businesses have been steadily growing. In this regard, STP is no longer considered effective or efficient because it cannot successfully meet those demands.
In the meantime, a spanning tree algorithm used in STP solves the problem of traffic looping by removing links that generate loops. However, this type of spanning tree algorithm has been denounced as having poor performance and being inefficient. In addition, in a network with communication paths generated by the spanning tree algorithm, some links are forced to be blocked even though they are usable, which leads to waste or, at least, inefficient use of bandwidths.
Moreover, if an error occurs on a predetermined link on a spanning tree, a communication path should be reestablished. In this case, convergence time, which generally amounts to about 30 seconds in the prior art, could be a serious setback for metropolitan area networks.